厚此薄彼

hòucǐbóbǐ
to favour one and discriminate against the other

CEDICT

to favour one and slight the other

Wiktionary

优厚某一方而冷落另一方。指对人或事不一视同仁，而有所偏颇。如：「政府查缉逃漏税不宜厚此薄彼，以免落人口实。」也作「厚彼薄此」。

重編國語辭典

指对人或事不一视同仁，而有所偏颇

維基詞典

Entry Composition

1 厚 hòu
  1. thick
  2. deep or profound
  3. kind
  4. generous
  5. rich or strong in flavor
  6. to favor
  7. to stress
2 此 cǐ this; these
3 薄 bó
  1. meager
  2. slight
  3. weak
  4. ungenerous or unkind
  5. frivolous
  6. to despise
  7. to belittle
  8. to look down on
  9. to approach or near
4 彼 bǐ
  1. that
  2. those
  3. (one) another